A typical automotive air conditioning system is located in an automotive engine compartment 1 of an automobile as shown in FIG. 1. An automotive air conditioning system 2 comprises a compressor 21, a condenser 22, a receiver-dryer 23, an evaporator (not shown), and a plurality of pipes 24 connecting the aforementioned components to each other to form a sealed refrigerant circuit. A refrigerant (not shown), such as freon, is disposed within the sealed circuit.
Plurality of pipes 24 includes a high-pressure side pipe 241, disposed between receiver-dryer 23 and the evaporator, for passing the refrigerant therethrough at a high pressure. Plurality of pipes 24 also includes a low-pressure side pipe 242, disposed between the evaporator and compressor 21, for passing the refrigerant therethrough at a low pressure. Pipes 241 and 242 respectively include valves 241a and 242a.
As shown in FIG. 2, valves 241a and 242a allow the refrigerant circuit to be filled, i.e. "charged", with refrigerant. Charging of the circuit is performed by coupling one end 100 (FIG. 2) of a refrigerant charging apparatus to valves 241a and 242a. The other end (not shown) of the refrigerant charging apparatus is coupled to a container (not shown) which stores the refrigerant. The charging apparatus charges the refrigeration circuit with the refrigerant from the container until a proper level of refrigerant is disposed within the circuit. Valves 241a and 242a close to prevent leakage of refrigerant when end 100 is removed.
More specifically, the refrigerant charging apparatus provides a typical connecting structure 103 which includes hoses 31 and 32 extending therefrom. Valves 31a and 32a are respectively set at the ends of hoses 31 and 32. Valves 31a and 32a are covered by caps 101 and 102 respectively when the charging apparatus is not in use. To perform the charging operation, caps 101 and 102 are removed and valves 31a and 32a are respectively coupled to valves 241a and 242a. During the charging operation, the refrigerant flows from the refrigerant charging apparatus into the refrigerant circuit through hoses 31 and 32 and valves 31a, 32a, 241a and 242a.
One problem with connecting structure 103 is the fact that mating valve pair 31a-241a must be coupled separately from mating valve pair 32a-242a. That is, the valve pairs must be coupled at different times. This separate coupling procedure requires a relatively long time.
Another problem with connecting structure 103 is that either one or both of valve pairs 31a-241a and 32a-242a may not mate securely. This unsecured mating may allow refrigerant to leak into and damage the atmosphere. Such a leak may also cause the charging apparatus to erroneously indicate that the circuit has been charged with a proper level of refrigerant. Additionally, if one or both of the valve pairs becomes uncoupled, the charging process is delayed while the uncoupled pair or pairs is recoupled.